SYSTEM AND METHODS FOR RAISED TOUCH SCREENS
A touch sensitive display assembly includes a touch screen and a button array. The touch screen is configured to display one or more input keys. The button array includes one or more buttons corresponding to the one or more input keys. The button array is formed by a substrate attached to a button membrane thereby creating a set of button cavities corresponding to the input keys. The button cavities are configured to be inflated and deflated by a pump coupled to a fluid reservoir. The cavities can be inflated/deflated together, in subsets, and/or individually. In some embodiments, the button array is sandwiched between a touch sensing layer and a display of the touch screen. In other embodiments, the button array can be located either above or below the touch screen.
This application is a continuation of U.S. patent application Ser. No. 14/242,312, filed 1 Apr. 2014, which is a continuation of U.S. patent application Ser. No. 14/014,014, filed on 29 Aug. 2013, which is a continuation of U.S. patent application Ser. No. 11/969,848, filed on 4 Jan. 2008, all of which are incorporated in their entireties by this reference.
BACKGROUND OF THE INVENTIONThis invention relates generally to touch sensitive displays. More particularly, this invention relates to cost effective systems and methods for selectively raising portions of touch sensitive displays.
Touch sensitive displays, e.g., touch screens, are very useful in applications where a user can input commands and data directly on a display. Common applications for touch screens include consumer products such as cellular telephones and user interfaces for industrial process control. Depending on their specific applications, these touch sensitive displays are commonly used in devices ranging from small handheld PDAs to large pieces of industrial equipment.
While it is convenient to be able to input and output data to and from the user on the same display, unlike a dedicated input device such as a keypad with discrete well-defined keys, most touch sensitive displays are generally flat. As a result, touch sensitive screens do not provide any tactile guidance for control “button(s)”. Instead, touch sensitive displays rely on visual guidance for user input.
Hence a serious drawback of touch sensitive displays is its inherent difficulty to input data accurately because adjacent buttons are not distinguishable by feel. Wrongly entered key strokes are common and the user is forced to keep his or her eyes on the display. The lack of tactile guidance is especially critical in industrial settings where potentially dangerous machines and parts are in constant motion such as an automobile assembly line, and also when operating the controls of a moving vehicle such as making a cellular telephone call while driving.
It is therefore apparent that an urgent need exists for an improved touch sensitive display which provides tactile guidance to the user that is easy to manufacture, easy to retrofit, shock resistant, impact resistant, remains compact and portable, cost effective, and durable.
SUMMARY OF THE INVENTIONTo achieve the foregoing and in accordance with the present invention, systems and methods for tactile guidance in touch sensitive screens are provided. Such touch screens can be operated very effectively and more safely without substantially increasing cost.
In one embodiment of the invention, a touch sensitive display assembly includes a touch screen and a button array. The touch screen is configured to display one or more input keys. The button array includes one or more buttons corresponding to the one or more input keys. The button array is formed by a substrate attached to a button membrane thereby creating a set of button cavities corresponding to the input keys.
The button cavities are configured to be inflated and deflated by a pump coupled to a fluid reservoir. The cavities can be inflated/deflated together, in subsets, and/or individually. In some embodiments, the button array is sandwiched between a touch sensing layer and a display of the touch screen. In other embodiments, the button array can be located either above or below the touch screen.
These and other features of the present invention will be described in more detail below in the detailed description of the invention and in conjunction with the following figures.
In order that the present invention may be more clearly ascertained, one embodiment will now be described, by way of example, with reference to the accompanying drawings, in which:
The present invention will now be described in detail with reference to several embodiments thereof as illustrated in the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent, however, to one skilled in the art, that the present invention may be practiced without some or all of these specific details. In other instances, well known process steps and/or structures have not been described in detail in order to not unnecessarily obscure the present invention. The features and advantages of the present invention may be better understood with reference to the drawings and discussions that follow.
Substrate 130 can be made from a suitable optically transparent material including polymers or glass, for example, elastomers, silicon-based organic polymers such as poly-dimethylsiloxane (PDMS), thermoset plastics such as polymethyl methacrylate (PMMA), and photocurable solvent resistant elastomers such as perfluropolyethers. In some embodiments, substrate 130 is a single homogenous layer approximately 1 mm to 0.1 mm thick and can be manufactured using well-known techniques for micro-fluid arrays to create one or more cavities and/or micro channels. It is also possible to construct substrate 130 using multiple layers from the same material or from different suitable materials.
Membrane no can be made from a suitable optically transparent and elastic material including polymers or silicon-based elastomers such as poly-dimethylsiloxane (PDMS) or polyethylene terephthalate (PET). In some embodiments, membrane is a single homogeneous layer less than 1 mm thick (preferably 50 to 200 microns) and can be manufactured using techniques known to one skilled in the art. It is also possible to construct membrane no using multiple layers from the same material or from different suitable materials. Membrane 110 can be attached to substrate 130 using a suitable adhesive, ultra-sonic bonding, oxygen plasma surface treatment or any other suitable techniques known to one skilled in the art.
Enclosed cavity 120, formed between substrate 130 and membrane 110, is fluid tight and coupled via a fluid channel 140 to one or more fluid pumps (not shown in
A suitable button fluid can be used to inflate exemplary cavity 120. To minimize optical distortion, the refractive index of the button fluid should be substantially similar to that of substrate 130 and also membrane 110. Depending on the application, suitable fluids include water and alcohols such isopropanol or methanol. It may also be possible to use an oil-based fluid such as Norland's index matching liquid (IML) 150 available from Norland Products of Cranbury, N.J.
Referring now to
It is also possible for display screen 280 to include sensors that provide input capability thereby eliminating the need for sensing layer 260. For example, an LCD with embedded optical sensors both touch screen and scanner functions was announced in a 2007 press release by Sharp Electronics of Japan.
As discussed above, button array 100 and sensing layer 460 may be attached directly to each other or array 100 and layer 460 may be operatively coupled to each other via a suitable intermediate solid or fluid material.
Button array 500 includes cavities 520a, 520b, 520c, 520d, 520e, 520f, 520g, 520h, 520k, 520m, 520n, 520p, 520q, 520r, while touch screen 600 is configured to able to display a set of corresponding input keys 620a, 620b, 620c, 620d, 620e, 620f, 620g, 620h, 620k, 620m, 620n, 620p, 620q, 620r. In this example, cavities 520a, 520b, 520c . . . 520r are overlaid on corresponding input keys 620a, 620b, 620c . . . 620r, using the exemplary techniques described above for the embodiments of
As shown in
Button array 500 is coupled to inflating fluid pump 572 and deflating fluid pump 576 via inlet fluid channel system 592 and outlet fluid channel system 596, respectively. In this example, fluid channel systems 592, 596 vary in width, i.e., wider in width nearer pumps 572, 576, in order to ensure fluid pressure and flow uniformity, in a manner similar to a human circulatory system.
Although the techniques discussed are applicable to many embodiments of the present invention, including the embodiments of
In this embodiment, inflating pump 572 is activated for a pre-determined period of time whenever cavities 520a, 520b, 520c . . . 520r need to be inflated. Note that deflating pump 576 remains “off” during inflation of cavities 520a, 520b, 520c . . . 520r. As a result, pump 572 is able to transfer fluid from fluid reservoir 574 to cavities 520a, 520b, 520c . . . 520r, until the required fluid pressure is accomplished. Inflating pump 572 is now deactivated, and both pumps 572, 576 are “off”. Fluid pressure is maintained in cavities 520a, 520b, 520c . . . 520r to keep them inflated.
Conversely, deflating pump 576 is activated for a pre-determined period of time whenever cavities 520a, 520b, 520c . . . 520r need to be deflated. Inflating pump 572 remains “off” during deflation of cavities 520a, 520b, 520c . . . 520r. As a result, deflating pump 576 is able to transfer fluid from cavities 520a, 520b, 520c . . . 520r back to fluid reservoir 574 to, until the required fluid pressure returns to the original value when deflating pump 576 is turned “off”.
Other pump configurations are also possible. For example, it is possible to replace pumps 572, 576 with a single bi-directional pump. It may also be possible to deflate cavities by opening value(s) to the fluid reservoir and let the fluid pressure decrease without the need for a separate deflating pump.
In step 840, touch sensing layer 260 senses the location(s) of the user's depressions on one or more of corresponding membrane portions 210a, 210b, 210c of button array 100. Touch sensing layer 260 then outputs the coordinate(s) of the sensed location(s) to processor 710 via touch screen controller 740 (step 840).
If processor 710 recognizes that the sensed location(s) correspond to an “EXIT” type key, for example, a “CALL” key or an “END” key in this exemplary telecom implementation, then button array 200 is deflated (step 860). Otherwise, touch sensing layer 260 continues to sense location(s) of subsequent user depression(s) and outputting the sensed location(s) coordinates to touch screen controller 740 (repeat step 840, 850).
Many modifications and additions are contemplated within the spirit of the present invention. For example, it is possible to add distortion correction capability to display screens 280, 380, 480 for correcting any optical distortion that may be introduced by button array 100. It may also be possible to include a set of pressure sensors coupled to each of the corresponding cavities of button array 100 thereby eliminating the need for touch sensing layers 260, 360, 460.
While the present invention has been described with reference to particular embodiments, it will be understood that the embodiments are illustrative and that the inventive scope is not so limited. In addition, the various features of the present invention can be practiced alone or in combination. Alternative embodiments of the present invention will also become apparent to those having ordinary skill in the art to which the present invention pertains. Such alternate embodiments are considered to be encompassed within the spirit and scope of the present invention. Accordingly, the scope of the present invention is described by the appended claims and is supported by the foregoing description.
Claims
1. A user interface system comprising:
- a flexible touch sensing layer defining a deformable region, defining a peripheral region adjacent the deformable region, and outputting signals corresponding to touch inputs on the deformable region and the peripheral region;
- a substrate coupled to the flexible touch sensing layer along a perimeter of the deformable region, cooperating with the deformable region to define a cavity, and defining a fluid channel fluidly coupled to the cavity;
- a displacement device displacing fluid into the cavity via the fluid channel to transition the deformable region from a deflated setting into an inflated setting, the deformable region substantially flush with the peripheral region in the deflated setting and elevated above the peripheral region in the inflated setting; and
- a processor detecting inputs on the flexible touch sensing layer proximal the deformable region in the deflated setting and in the inflated setting according to outputs of the flexible touch sensing layer.
Type: Application
Filed: May 18, 2015
Publication Date: Sep 3, 2015
Inventor: Craig M. Ciesla (Fremont, CA)
Application Number: 14/715,318